Cachrys ferulacea (L.) Calest. Extracts as Natural Photosensitizers: An In Vitro Photobiological Study

The Cachrys genus (Apiaceae) is widely distributed in the Mediterranean Basin. Previous studies highlighted the photobiological properties of different Cachrys species, such as C. pungens Jan, C. libanotis L. and C. sicula L. Based on these promising previous results, and in order to continue exploring such interesting genus, the aim of this study was to evaluate the photocytotoxic activity of extracts from Cachrys ferulacea (L.) Calest. Aerial parts were collected in Calabria (Southern Italy) and extracted through three different techniques: traditional maceration, pressurized cyclic solid-liquid (PCSL) extraction using Naviglio extractor® and supercritical CO₂. The phytochemical composition was assessed with gas chromatography-mass spectrometry (GC-MS) and the photocytotoxic potential of samples was evaluated on UVA-irradiated C32 melanoma cell line. The apoptotic responses on treated cells were also assessed. Furthermore, the phenolic and flavonoid content and the in vitro antioxidant activity were also estimated. Different coumarins were identified and quantified. All the extracts affected cell viability in a concentration-dependent manner after irradiation with UVA light for 1 hour at a dose of 1.08 J/cm². Sample obtained through supercritical CO₂ extraction showed the highest activity, with an IC₅₀ value equal to 4.91 μg/mL. This study could provide a starting point for further researches focusing on new photosensitizing agents useful in cancer photochemotherapy.